Clutch device for washing machines

ABSTRACT

Disclosed herein is a clutch device for washing machines. The clutch device comprises a washing shaft for transmitting a rotating force to a pulsator, a dewatering shaft disposed along the outer circumference of the washing shaft in a coaxial fashion for transmitting the rotating force to a washing tub, and a spiral spring, having one end fixedly connected to the washing shaft and the other end fixedly connected to the dewatering shaft, for transmitting the rotating force from the washing shaft to the dewatering shaft when the spiral spring comes into tight contact with the washing shaft or the dewatering shaft as the washing shaft is rotated. Consequently, the present invention has the effect of simplifying the overall structure of the clutch device. The clutch device further comprises a friction member attached to the washing shaft or the dewatering shaft for generating a frictional force when the spiral spring is extended or compressed. Consequently, the present invention has the effect of decreasing wear of the washing shaft and dewatering shaft, with which the spiral spring is in tight contact, and of improving efficiency of rotating force transmission.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a clutch device for washing machines, and, more particularly, to a clutch device, having a simple structure, that is capable of allowing a rotating force to be transmitted from a driving motor to a dewatering shaft or stopping the rotating force from being transmitted from the driving motor to the dewatering shaft through the use of a spiral spring fixedly connected between a washing shaft and the dewatering shaft.

2. Description of the Related Art

FIG. 1 is a sectional view illustrating a conventional clutch device for washing machines.

As shown in FIG. 1, the conventional clutch device for washing machines comprises a pulley 55 that is rotated by a motor (not shown), to which the pulley 55 is connected via a belt (not shown). The pulley 55 is directly connected to an inner shaft 60. Along the outer circumference of the inner shaft 60 is disposed a hollow outer shaft 61. The inner shaft 60 is connected to a washing shaft 64 via a speed-reduction member 62 disposed at the upper end of the inner shaft 60. To the upper end of the washing shaft 64 is attached a pulsator 54. Also, the outer shaft 61 is directly connected to a brake drum 63, which protects the speed-reduction member 62. The brake drum 63 is directly connected to a dewatering shaft 65, which is attached to the lower end of a washing tub 53 disposed in a water tub 52.

To the outer circumferential surface of the brake drum 63 is attached a brake band 71. The brake band 71 has a free end connected to a brake lever 70, which is disposed at the outside of a lower case 50. To the brake lever 70 is linked a clutch lever 80. Above the pulley 55 is disposed a clutch 81, which is manipulated by the clutch lever 80.

In the clutch 81 is disposed a clutch spring 82. The lower end of the clutch spring 82 is connected to the outer circumferential surface of a clutch block 83, which is connected to the inner shaft 60.

The clutch device with the above-stated construction is operated as follows: when the brake lever 70 is pulled during a dewatering operation of the washing machine, the brake drum 63 is released, and at the same time, the clutch lever 80 is also pulled. At this time, the clutch 81, which has been restricted by the clutch lever 80, is released. As a result, the clutch block 83 is connected to the outer shaft 61 by the clutch spring 82. Consequently, the inner and outer shafts 60 and 61 are rotated together. At this time, the washing tub 53 is rotated in high speed such that the dewatering operation of the washing machine is carried out.

When the pulley 55 is rotated in alternating directions by the motor during a washing operation of the washing machine, the inner shaft 60 is also rotated in alternating directions by the clutch device with the above-stated construction. At this time, the pulsator 54 is rotated in alternating directions, while the rotating speed of the washing shaft 64 is reduced by the speed-reduction member 62, to generate a rotary stream of water.

During the dewatering operation of the washing machine, wash water is drained. At this time, when the wire is pulled as the motor is rotated, the brake lever 70 and the clutch lever 80 are also pulled, and therefore, the brake drum 63 and the clutch 81 are released. In this state, when the pulley 55 is rotated in high speed as the motor is operated, the inner and outer shafts 60 and 61 are rotated together by the clutch spring 82 disposed in the clutch 81, and therefore, the brake drum 63, which is now free from restriction by the brake band 71, the washing shaft 64, and the dewatering shaft 65 are rotated together in high speed. At this time, the washing tub 53 is rotated in high speed such that moisture is centrifugally removed from the laundry.

In the conventional clutch device for washing machines with the above-stated construction, however, not only the brake lever 70 and the clutch lever 80 but also the brake drum 63, the brake band 71, and the clutch 81 are necessary to perform the rotating force switching operation as described above. As a result, the overall clutch operating structure is complicated, the number of components constituting the conventional clutch device for washing machines is increased. Consequently, the manufacturing costs of the conventional clutch device for washing machines. Especially, the conventional clutch device for washing machines has a problem in that noise is increased when the brake is operated.

SUMMARY OF THE INVENTION

Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a clutch device for washing machines, which has a simple structure and is manufactured with reduced manufacturing costs.

It is another object of the present invention to provide a clutch device for washing machines having a friction member that is capable of decreasing wear, noise, and vibration due to friction between a spring and a dewatering shaft and between the spring and a washing shaft during a dewatering operation of the washing machine, and of improving efficiency of rotating force transmission.

In accordance with one aspect of the present invention, the above and other objects can be accomplished by the provision of a clutch device for washing machines, comprising: a washing shaft for transmitting a rotating force to a pulsator; a dewatering shaft disposed along the outer circumference of the washing shaft in a coaxial fashion for transmitting the rotating force to a washing tub; and a spiral spring, having one end fixedly connected to the washing shaft and the other end fixedly connected to the dewatering shaft, for transmitting the rotating force from the washing shaft to the dewatering shaft when the spiral spring comes into tight contact with the washing shaft or the dewatering shaft as the washing shaft is rotated.

In accordance with another aspect of the present invention, there is provided a clutch device for washing machines, comprising: a washing shaft for transmitting a rotating force to a pulsator; a dewatering shaft disposed along the outer circumference of the washing shaft in a coaxial fashion for transmitting the rotating force to a washing tub; a spiral spring having one end fixedly connected to the washing shaft or the dewatering shaft, the spiral spring being extended or compressed as the washing shaft is rotated; a spring fixing part formed in the shape of a hollow cylinder, the spring fixing part being disposed between the washing shaft and the dewatering shaft, while the other end of the spiral spring, fixedly connected to neither the washing shaft nor the dewatering shaft, is fixedly connected to the spring fixing part, for transmitting the rotating force from the washing shaft to the dewatering shaft when the spiral spring comes into tight contact with the spring fixing part as the spiral spring is extended or compressed; and a friction member disposed between the spring fixing part and the washing shaft or the dewatering shaft, to which the spiral spring is fixedly connected, for generating a frictional force.

In accordance with yet another aspect of the present invention, there is provided a clutch device for washing machines, comprising: a washing shaft for transmitting a rotating force to a pulsator; a dewatering shaft disposed along the outer circumference of the washing shaft in a coaxial fashion for transmitting the rotating force to a washing tub; a clutch connection device connected between a first set consisting of the pulsator and the washing shaft and a second set consisting of the dewatering shaft for transmitting the rotating force from the first or second set to the second or first set when the first or second set is rotated more than predetermined revolutions in one direction; and a friction member attached to at least one of the washing shaft, the dewatering shaft, and the clutch connection device for generating a frictional force when the rotating force is transmitted by the clutch connection device.

According to the clutch device for washing machines with the above-stated construction according to the present invention, the spiral spring is disposed between the washing shaft and the dewatering shaft for transmitting a rotating force to the dewatering shaft. Consequently, the present invention has the effect of simplifying the overall structure of the clutch device and reducing the manufacturing costs of the clutch device.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a sectional view illustrating a conventional clutch device for washing machines;

FIG. 2 is a sectional view, cut away in part, illustrating a washing machine with a clutch device according to a first preferred embodiment of the present invention;

FIG. 3 is a longitudinal sectional view illustrating the clutch device according to the first preferred embodiment of the present invention shown in FIG. 2 in a neutral position;

FIG. 4 is a cross-sectional view illustrating the clutch device according to the first preferred embodiment of the present invention shown in FIG. 2 in the neutral position;

FIG. 5 is a longitudinal sectional view illustrating the clutch device according to the first preferred embodiment of the present invention shown in FIG. 2 in the state that a washing shaft is rotated in the clockwise direction;

FIG. 6 is a cross-sectional view illustrating the clutch device according to the first preferred embodiment of the present invention shown in FIG. 2 in the state that the washing shaft is rotated in the clockwise direction;

FIG. 7 is a longitudinal sectional view illustrating the clutch device according to the first preferred embodiment of the present invention shown in FIG. 2 in the state that the washing shaft is rotated in the counterclockwise direction;

FIG. 8 is a cross-sectional view illustrating the clutch device according to the first preferred embodiment of the present invention shown in FIG. 2 in the state that the washing shaft is rotated in the counterclockwise direction;

FIG. 9 is a sectional view, cut away in part, illustrating a washing machine with a clutch device according to a second preferred embodiment of the present invention;

FIG. 10 is a sectional view, cut away in part, illustrating a washing machine with a clutch device according to a third preferred embodiment of the present invention;

FIG. 11 is a cross-sectional view illustrating the clutch device according to the third preferred embodiment of the present invention shown in FIG. 10;

FIG. 12 is a sectional view, cut away in part, illustrating a washing machine with a clutch device according to a fourth preferred embodiment of the present invention;

FIG. 13 is a cross-sectional view illustrating the clutch device according to the fourth preferred embodiment of the present invention shown in FIG. 12; and

FIG. 14 is a sectional view, cut away in part, illustrating a washing machine with a clutch device according to a fifth preferred embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a sectional view, cut away in part, illustrating a washing machine with a clutch device according to a first preferred embodiment of the present invention.

As shown in FIG. 2, the clutch device for washing machines according to the first preferred embodiment of the present invention comprises: a water tub 12 for storing wash water; a washing tub 14 rotatably disposed in the water tub 12 for washing, rinsing, and dewatering the laundry; a pulsator 16 attached to a boss part 17 disposed at the center of the inner bottom part of the washing tub 14 for performing rotating movement in alternating directions to generate washing stream of water, by which the laundry is washed; and a driving motor 26 for supplying a rotating force to a dewatering shaft 22 and a washing shaft 24 such that the washing tube 14 and the pulsator 16 are rotated.

The dewatering shaft 22 is formed in the shape of a hollow cylinder such that the washing shaft 24 is longitudinally inserted in the dewatering shaft 22 in a coaxial fashion. The dewatering shaft 22 is fixedly connected to the washing tub 14 such that the rotating force is transmitted from the driving motor 26 to the dewatering shaft 22, during the dewatering operation of the washing machine, to rotate the washing tub 14.

The washing shaft 24 is inserted through the dewatering shaft 22. The upper end of the washing shaft 24 is fixedly connected to a pulsator bush 18, to which the pulsator 16 is fixed, and the lower end of the washing shaft 24 is connected to the driving motor 26. Consequently, the pulsator 16 is rotated in alternating directions when the rotating force from the driving motor is transmitted to the washing shaft 24.

Between the upper and lower parts of the washing shaft 24 is disposed a gear train 25 comprising planet gears for reducing the speed of the rotating force from the driving motor to the pulsator 16.

The clutch device according to the first preferred embodiment of the present invention is provided with a spiral spring 36, which comes into tight contact with any one of the washing shaft 24 and the dewatering shaft 22, when the washing shaft 24 is rotated several revolutions in one direction, for transmitting the rotating force from the washing shaft 24 to the dewatering shaft 22.

Between the outer circumferential surface of the washing shaft 24, to which one end of the spiral spring 36 is fixedly connected, and the spiral spring 36 is disposed a friction member 34, which prevents the spiral spring 36 from coming into direct contact with the outer circumferential surface of the washing shaft 24 when the spiral spring 36 is compressed. Specifically, the friction member 34 is attached to the outer circumferential surface of the washing shaft 24.

Between the inner circumferential surface of the dewatering shaft 22, to which the other end of the spiral spring 36 is fixedly connected, and the spiral spring 36 is disposed a friction member 32, which prevents the spiral spring 36 from coming into direct contact with the inner circumferential surface of the dewatering shaft 22 when the spiral spring 36 is extended. Specifically, the friction member 32 is attached to the inner circumferential surface of the dewatering shaft 22.

The spiral spring 36 is disposed around the washing shaft 24. Preferably, the spiral spring 36 is made of a plate-shaped material having high durability and elasticity.

Specifically, the inner end of the spiral spring 36 is securely connected to a ring-shaped groove part 34 a of the friction member 34 attached to the outer circumferential surface of the washing shaft 24, and the outer end of the spiral spring 36 is securely connected to a ring-shaped groove part 32 a of the friction member 32 attached to the outer circumferential surface of the dewatering shaft 22 (See FIG. 3). Consequently, it is not necessary to provide additional members for fixing the spiral spring 36 to the washing shaft 24 and the dewatering shaft 22, and therefore, the manufacturing costs of the clutch device for washing machines are reduced.

The operation of the clutch device for washing machines with the above-stated construction according to the first preferred embodiment of the present invention will now be described in detail.

FIGS. 3 to 8 shows the clutch device for washing machines according to the first preferred embodiment of the present invention. FIG. 3 is longitudinal sectional view illustrating the clutch device for washing machines in a neutral position, FIG. 4 is a cross-sectional view illustrating the clutch device for washing machines in the neutral position, FIG. 5 is a longitudinal sectional view illustrating the clutch device for washing machines in the state that the washing shaft is rotated in the clockwise direction, FIG. 6 is a cross-sectional view illustrating the clutch device for washing machines in the state that the washing shaft is rotated in the clockwise direction, FIG. 7 is a longitudinal sectional view illustrating the clutch device for washing machines in the state that the washing shaft is rotated in the counterclockwise direction, and FIG. 8 is a cross-sectional view illustrating the clutch device for washing machines in the state that the washing shaft is rotated in the counterclockwise direction.

When the washing machine is not operated, as shown in FIGS. 3 and 4, the spiral spring 36 is neither compressed nor extended.

During a washing operation of the washing machine, a stirring washing process is carried out by the pulsator 16 in the above-mentioned state. Specifically, the washing shaft 24 is repeatedly rotated in alternating directions by the driving motor 26, and therefore, the pulsator 16 is also repeatedly rotated in alternating directions to carry out the stirring washing process.

As described above, one end of the spiral spring 36 is connected to the washing shaft 24, and the other end of the spiral spring 36 is connected to the dewatering shaft 22. Consequently, when the washing shaft 24 is rotated more than predetermined revolutions in the forward direction, the spiral spring 36 is maximally extended, as shown in FIGS. 5 and 6. As a result, the spiral spring 36 comes into tight contact with the friction member 32 attached to the inner circumferential surface of the dewatering shaft 22.

When the washing shaft 24 is rotated more than predetermined revolutions in the reverse direction, on the other hand, the spiral spring 36 is maximally compressed, as shown in FIGS. 7 and 8. As a result, the spiral spring 36 comes into tight contact with the friction member 34 attached to the outer circumferential surface of the washing shaft 24.

In the maximally extended and compressed states, the washing shaft 24 is tightly coupled to the dewatering shaft 22 by the spiral spring 36. As a result, the rotating force from the washing shaft 24 is transmitted to the dewatering shaft 22 through the spiral spring 36, and therefore, the washing tub 14 is rotated along with the pulsator 16.

Consequently, it is preferable to rotate the washing shaft 24 in alternating directions, such that the rotating direction of the washing shaft 24 is changed before the spiral spring is maximally extended or maximally compressed, i.e., before the rotating force from the washing shaft 24 is transmitted to the dewatering shaft 22, to carry out the stirring washing process.

While the pulsator 16 is rotated in alternating directions to carry out the stirring washing process, shocks generated from the pulsator 16 are absorbed by the pulsator 16, since the pulsator 16 has high elasticity. Consequently, the pulsator 16 is smoothly rotated in alternating directions, and therefore, the noise during the rotation of the pulsator 16 is reduced, and at the same time, the driving force is reduced.

After the washing or rinsing operation of the washing machine is completed, a dewatering operation of the washing machine is initiated. When the washing shaft 24 is continuously rotated in one direction, the spiral spring 36 is maximally extended, as shown in FIGS. 5 and 6, or is maximally compressed, as shown in FIGS. 7 and 8. As a result, the spiral spring 36 comes into tight contact with the friction member 32 attached to the outer circumferential surface of the dewatering shaft 22 or the friction member 34 attached to the outer circumferential surface of the washing shaft 24, and therefore, the washing shaft 24 is tightly coupled to the dewatering shaft 22 by the spiral spring 36.

Consequently, the rotating force from the washing shaft 24 is transmitted to the washing tub 14 through the dewatering shaft 24, and therefore, the dewatering operation of the washing machine is normally carried out by the high-speed rotation of the washing tub 14.

FIG. 9 is a sectional view, cut away in part, illustrating a washing machine with a clutch device according to a second preferred embodiment of the present invention.

The clutch device for washing machines according to the second preferred embodiment of the present invention is identical in construction and operation to the clutch device for washing machines according to the first preferred embodiment of the present invention except that the clutch device for washing machines further comprises: a spiral spring 37, which is made of a coil instead of the plate-shaped material, as shown in FIG. 9. Therefore, other components of the clutch device for washing machines according to the second preferred embodiment of the present invention, which correspond to those of the clutch device for washing machines according to the first preferred embodiment of the present invention, are indicated by the same reference numerals as those of the clutch device for washing machines according to the first preferred embodiment of the present invention, and a detailed description thereof will not be given.

FIG. 10 is a sectional view, cut away in part, illustrating a washing machine with a clutch device according to a third preferred embodiment of the present invention, and FIG. 11 is a cross-sectional view illustrating the clutch device according to the third preferred embodiment of the present invention shown in FIG. 10.

As shown in FIGS. 10 and 11, the clutch device for washing machines according to the third preferred embodiment of the present invention further comprises: a spring fixing part 38 disposed between the washing shaft 24 and the dewatering shaft 22 in addition to the washing shaft 24, the dewatering shaft 22, the spiral spring 36, and the friction member 32, which constitute the clutch device for washing machines according to the first preferred embodiment of the present invention.

The inner end of the spiral spring 36 is securely connected to a ring-shaped groove part 24 a formed at the outer circumferential surface of the washing shaft 24 such that the spiral spring 36 is extended or compressed as the washing shaft 24 is rotated.

The spring fixing part 38, which is formed in the shape of a hollow cylinder, is disposed between the washing shaft 24 and the dewatering shaft 22. The outer end of the spiral spring 36 is securely connected to a ring-shaped groove part 38a formed at the inner circumferential surface of the spring fixing part 38.

The friction member 32 is disposed between the outer circumferential surface of the spring fixing part 38 and the inner circumferential surface of the dewatering shaft 22 while the friction member 32 is in frictional contact with the outer circumferential surface of the spring fixing part 38 and the inner circumferential surface of the dewatering shaft 22. The friction surface of the friction member 32, which is in frictional contact with the spring fixing part 38, is fixed to the spring fixing part 38. If the friction member 32 is fixed to the outer circumferential surface of the spring fixing part 38 or the inner circumferential surface of the dewatering shaft 22, the clutch device for washing machines is more easily assembled.

The operation of the clutch device for washing machines with the above-stated construction according to the third preferred embodiment of the present invention will now be described in detail.

During a washing operation of the washing machine, a stirring washing process is carried out by the pulsator 16 in the above-mentioned state. Specifically, the washing shaft 24 is repeatedly rotated in alternating directions by the driving motor 26, and therefore, the pulsator 16 is also repeatedly rotated in alternating directions to carry out the stirring washing process.

As described above, the spring fixing part 38 is connected to the washing shaft 24 by the spiral spring 36, and the spring fixing part 38 is also connected to the dewatering shaft 22 by the friction member 32. Consequently, when the washing shaft 24 is rotated more than predetermined revolutions in the forward direction, the spiral spring 36 is maximally extended. When the washing shaft 24 is rotated more than predetermined revolutions in the reverse direction, on the other hand, the spiral spring 36 is maximally compressed.

When the washing shaft 24 is rotated in alternating directions between the maximally extended state and the maximally compressed state, and therefore, the pulsator 16 is also rotated in alternating directions to carry out the stirring washing process, the friction member 32 attached to the spring fixing part 38 comes into tight contact with the dewatering shaft 22 due to the friction between the friction member 32 attached to the spring fixing part 38 and the dewatering shaft 22. Consequently, the spring fixing part 38 is rotated along with the washing shaft 24, and therefore, the spiral spring 36 is compressed and extended in the dewatering shaft 22.

After the washing or rinsing operation of the washing machine is completed, a dewatering operation of the washing machine is initiated. When the washing shaft 24 is continuously rotated in one direction, the spiral spring 36 is maximally extended or maximally compressed. As a result, the dewatering shaft 22 is rotated along with the washing shaft 24 by the friction member 32 attached to the outer circumferential surface of the spring fixing part 38, which is rotated along with the washing shaft 24 and the spiral spring 36. Consequently, the rotating force from the washing shaft 24 is transmitted to the dewatering shaft 24, and therefore, the washing tub 14 is also rotated to normally carry out the dewatering operation of the washing machine.

When the washing shaft 24 is rotated along with the dewatering shaft 22, slippage occurs between the friction member 32 attached to the outer circumferential surface of the spring fixing part 38 and the dewatering shaft 22, and the friction member 32 is deformed. Consequently, friction between the spring fixing part 38 and the dewatering shaft 22 is prevented, and therefore, the durability of the clutch device for washing machines is increased. Furthermore, vibration and noise, generated when the washing shaft 24 is rotated along with the dewatering shaft 22, are reduced.

FIG. 12 is a sectional view, cut away in part, illustrating a washing machine with a clutch device according to a fourth preferred embodiment of the present invention, and FIG. 13 is a cross-sectional view illustrating the clutch device according to the fourth preferred embodiment of the present invention shown in FIG. 12.

As shown in FIGS. 12 and 13, the clutch device for washing machines according to the fourth preferred embodiment of the present invention further comprises: a spring fixing part 39 disposed between the washing shaft 24 and the dewatering shaft 22 in addition to the washing shaft 24, the dewatering shaft 22, the spiral spring 36, and the friction member 34, which constitute the clutch device for washing machines according to the first preferred embodiment of the present invention.

The outer end of the spiral spring 36 is securely connected to a ring-shaped groove part 22 a formed at the inner circumferential surface of the dewatering shaft 22 such that the spiral spring 36 is extended or compressed as the washing shaft 24 is rotated.

The spring fixing part 39, which is formed in the shape of a hollow cylinder, is disposed between the washing shaft 24 and the dewatering shaft 22. The inner end of the spiral spring 36 is securely connected to a ring-shaped groove part 39a formed at the outer circumferential surface of the spring fixing part 39.

The friction member 34 is disposed between the inner circumferential surface of the spring fixing part 39 and the inner circumferential surface of the washing shaft 24 while the friction member 34 is in frictional contact with the inner circumferential surface of the spring fixing part 39 and the inner circumferential surface of the washing shaft 24. The friction surface of the friction member 34, which is in frictional contact with the spring fixing part 39, is fixed to the spring fixing part 39. If the friction member 34 is fixed to the inner circumferential surface of the spring fixing part 39 or the outer circumferential surface of the washing shaft 24, the clutch device for washing machines is more easily assembled.

The operation of the clutch device for washing machines with the above-stated construction according to the fourth preferred embodiment of the present invention will now be described in detail.

During a washing operation of the washing machine, a stirring washing process is carried out by the pulsator 16 in the above-mentioned state. Specifically, the washing shaft 24 is repeatedly rotated in alternating directions by the driving motor 26, and therefore, the pulsator 16 is also repeatedly rotated in alternating directions to carry out the stirring washing process.

As described above, the spring fixing part 39 is connected to the washing shaft 24 by the friction member 34, and the spring fixing part 39 is also connected to the dewatering shaft 22 by the spiral spring 36. Consequently, when the washing shaft 24 is rotated more than predetermined revolutions in the forward direction, the spiral spring 36 is maximally extended. When the washing shaft 24 is rotated more than predetermined revolutions in the reverse direction, on the other hand, the spiral spring 36 is maximally compressed.

When the washing shaft 24 is rotated in alternating directions between the maximally extended state and the maximally compressed state, and therefore, the pulsator 16 is also rotated in alternating directions to carry out the stirring washing process, the friction member 34 attached to the spring fixing part 39 comes into tight contact with the washing shaft 24 due to the friction between the friction member 34 attached to the spring fixing part 39 and the washing shaft 24. Consequently, the spring fixing part 39 is rotated along with the washing shaft 24, and therefore, the spiral spring 36 is compressed and extended in the dewatering shaft 22.

After the washing or rinsing operation of the washing machine is completed, a dewatering operation of the washing machine is initiated. When the washing shaft 24 is continuously rotated in one direction, the spiral spring 36 is maximally extended or maximally compressed. As a result, the dewatering shaft 22 is rotated along with the washing shaft 24 by the friction member 34 attached to the inner circumferential surface of the spring fixing part 39, which is rotated along with the washing shaft 24 and the spiral spring 36. Consequently, the rotating force from the washing shaft 24 is transmitted to the dewatering shaft 24, and therefore, the washing tub 14 is also rotated to normally carry out the dewatering operation of the washing machine.

When the washing shaft 24 is rotated along with the dewatering shaft 22, slippage occurs between the friction member 34 attached to the inner circumferential surface of the spring fixing part 39 and the washing shaft 24, and the friction member 34 is deformed. Consequently, friction between the spring fixing part 39 and the washing shaft 24 is prevented, and therefore, the durability of the clutch device for washing machines is increased. Furthermore, vibration and noise, generated when the washing shaft 24 is rotated along with the dewatering shaft 22, are reduced.

FIG. 14 is a sectional view, cut away in part, illustrating a washing machine with a clutch device according to a fifth preferred embodiment of the present invention.

The clutch device for washing machines according to the fifth preferred embodiment of the present invention is identical in construction and operation to the clutch device for washing machines according to the first preferred embodiment of the present invention except that the clutch device for washing machines further comprises: a clutch connection elastic member connected between the washing shaft 24 and the dewatering shaft 22 for transmitting the rotating force from the washing shaft to the dewatering shaft 22 when the washing shaft 24 is rotated more than predetermined revolutions in one direction, as shown in FIG. 14. Therefore, other components of the clutch device for washing machines according to the second preferred embodiment of the present invention, which correspond to those of the clutch device for washing machines according to the first preferred embodiment of the present invention, are indicated by the same reference numerals as those of the clutch device for washing machines according to the first preferred embodiment of the present invention, and a detailed description thereof will not be given.

The clutch connection elastic member comprises a coil spring 46 disposed around the washing shaft 24. The washing shaft 24 and the dewatering shaft 22 are provided with elastic member mounting rings 44 and 42, respectively, to which both ends of the coil spring 46 are fixedly mounted, respectively.

The elastic member mounting rings 44 and 42 are each formed in the shape of a circular ring such that the inner circumferential surfaces of the elastic member mounting rings 44 and 42 come into tight contact with the washing shaft 24 and the dewatering shaft 22. Between the elastic member mounting rings 44 and 42 is preferably disposed a ring-shaped spacer 43 for uniformly maintaining the vertical distance between the elastic member mounting rings 44 and 42.

On the outer surfaces of the elastic member mounting rings 44 and 42 and the ring-shaped spacer 43 are disposed a friction member 49, with which the coil spring 46 comes into frictional contact when the coil spring 46 is compressed. On the inner circumferential surface of the boss part 17 is another friction member 48, with which the coil spring 46 also comes into frictional contact when the coil spring 46 is compressed.

The operation of the clutch device for washing machines with the above-stated construction according to the fifth preferred embodiment of the present invention will now be described in detail.

During a washing operation of the washing machine, a stirring washing process is carried out by the pulsator 16 in the above-mentioned state. Specifically, the washing shaft 24 is repeatedly rotated in alternating directions by the driving motor 26, and therefore, the pulsator 16 is also repeatedly rotated in alternating directions to carry out the stirring washing process.

As described above, the washing shaft 24 and the dewatering shaft 22 are connected to each other by the coil spring 46. Consequently, when the washing shaft 24 is rotated more than predetermined revolutions in the forward direction, the coil spring 46 is maximally extended. When the washing shaft 24 is rotated more than predetermined revolutions in the reverse direction, on the other hand, the coil spring 46 is maximally compressed.

When the pulsator 16 is rotated in alternating directions to carry out the stirring washing process, the coil spring 46 is prevented from coming into frictional contact with the outer circumferential surfaces of the elastic member mounting rings 44 and 42 and the ring-shaped spacer 43 by the friction member 49 and with the inner circumferential surface of the boss part 17 by the friction member 48. Consequently, the durability of the clutch device for washing machines is increased, and vibration and noise are reduced.

After the washing or rinsing operation of the washing machine is completed, a dewatering operation of the washing machine is initiated. When the washing shaft 24 is continuously rotated in one direction, the coil spring 46 is maximally extended or maximally compressed. As a result, the rotating force from the washing shaft 24 is transmitted to the dewatering shaft 24, and therefore, the washing tub 14 is also rotated to normally carry out the dewatering operation of the washing machine.

In the above-described fifth embodiment of the present invention, coupling between the washing shaft 22 and the dewatering shaft 24 is improved by the provisions of the friction members 48 and 49, and therefore, efficiency of the rotating force transmission is improved.

As apparent from the above description, the present invention has the following effects.

The clutch device for washing machines according to the first or second preferred embodiment of the present invention includes the spiral spring, coming into frictional contact with the washing shaft and the dewatering shaft, for transmitting the rotating force from the washing shaft to the dewatering shaft. Consequently, the present invention has the effect of simplifying the overall structure of the clutch device and reducing the manufacturing costs of the clutch device.

Also, the clutch device for washing machines according to the first or second preferred embodiment of the present invention includes the friction members for decreasing wear due to friction between the spiral spring and the dewatering shaft and between the spiral spring and the washing shaft during the dewatering operation of the washing machine. Consequently, the present invention has the effect of improving durability of the clutch device, of reducing noise and vibration generated from the clutch device, and of improving efficiency of the rotating force transmission of the clutch device.

The clutch device for washing machines according to the third or fourth preferred embodiment of the present invention includes the spring fixing part, which is formed in the shape of a hollow cylinder and to which one end of the spiral spring is fixedly connected, for maximizing the frictional force generated between the spring fixing part and the friction members. Consequently, the present invention has the effect of effectively reducing wear, noise, and vibration of the components of the clutch device generated when the washing shaft is rotated along with the dewatering shaft.

The clutch device for washing machines according to the fifth preferred embodiment of the present invention includes the friction member disposed between the outer circumferential surfaces of the elastic member mounting rings and the ring-shaped spacer and the coil spring for preventing the coil spring from coming into frictional contact with the outer circumferential surfaces of the elastic member mounting rings and the ring-shaped spacer. Consequently, the present invention has the effect of improving durability of the clutch device and of reducing noise and vibration generated from the clutch device.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

The present disclosure relates to subject matter contained in Korean Application No. 10-2004-81693, filed on Oct. 13, 2004, the contents of which are herein expressly incorporated by reference in its entirety. 

1. A clutch device for washing machines, comprising: a washing shaft for transmitting a rotating force to a pulsator; a dewatering shaft disposed along the outer circumference of the washing shaft in a coaxial fashion for transmitting the rotating force to a washing tub; and a spiral spring, having one end fixedly connected to the washing shaft and the other end fixedly connected to the dewatering shaft, for transmitting the rotating force from the washing shaft to the dewatering shaft when the spiral spring comes into tight contact with the washing shaft or the dewatering shaft as the washing shaft is rotated.
 2. The device as set forth in claim 1, wherein at least one of the washing shaft, the dewatering shaft, and the spiral spring is provided with a friction member for generating a frictional force when the spiral spring is extended or compressed.
 3. The device as set forth in claim 2, wherein the friction member is attached to the inner circumferential surface of the dewatering shaft at the position where the spiral spring comes into frictional contact with the dewatering shaft when the spiral spring is extended.
 4. The device as set forth in claim 3, wherein the spiral spring is fixedly connected to the friction member.
 5. The device as set forth in claim 3, wherein the spiral spring comes into tight contact with the friction member when the spiral spring is maximally extended.
 6. The device as set forth in claim 2, wherein the friction member is attached to the outer circumferential surface of the washing shaft at the position where the spiral spring comes into frictional contact with the washing shaft when the spiral spring is compressed.
 7. The device as set forth in claim 6, wherein the spiral spring is fixedly connected to the friction member.
 8. The device as set forth in claim 6, wherein the spiral spring comes into tight contact with the friction member when the spiral spring is maximally compressed.
 9. A clutch device for washing machines, comprising: a washing shaft for transmitting a rotating force to a pulsator; a dewatering shaft disposed along the outer circumference of the washing shaft in a coaxial fashion for transmitting the rotating force to a washing tub; a spiral spring having one end fixedly connected to the washing shaft or the dewatering shaft, the spiral spring being extended or compressed as the washing shaft is rotated; a spring fixing part formed in the shape of a hollow cylinder, the spring fixing part being disposed between the washing shaft and the dewatering shaft, while the other end of the spiral spring, fixedly connected to neither the washing shaft nor the dewatering shaft, is fixedly connected to the spring fixing part, for transmitting the rotating force from the washing shaft to the dewatering shaft when the spiral spring comes into tight contact with the spring fixing part as the spiral spring is extended or compressed; and a friction member disposed between the spring fixing part and the washing shaft or the dewatering shaft, to which the spiral spring is fixedly connected, for generating a frictional force.
 10. The device as set forth in claim 9, wherein one end of the spiral spring is fixedly connected to the washing shaft, and the other end of the spiral spring is fixedly connected to the inner circumferential surface of the spring fixing part.
 11. The device as set forth in claim 10, wherein the friction member is attached to the outer circumferential surface of the spring fixing part or the inner circumferential surface of the dewatering shaft.
 12. The device as set forth in claim 11, wherein the frictional force is generated between the washing shaft and the friction member when the spiral spring is maximally compressed.
 13. The device as set forth in claim 9, wherein one end of the spiral spring is fixedly connected to the dewatering shaft, and the other end of the spiral spring is fixedly connected to the outer circumferential surface of the spring fixing part.
 14. The device as set forth in claim 13, wherein the friction member is attached to the inner circumferential surface of the spring fixing part or the outer circumferential surface of the washing shaft.
 15. The device as set forth in claim 14, wherein the frictional force is generated between the dewatering shaft and the friction member when the spiral spring is maximally extended.
 16. A clutch device for washing machines, comprising: a washing shaft for transmitting a rotating force to a pulsator; a dewatering shaft disposed along the outer circumference of the washing shaft in a coaxial fashion for transmitting the rotating force to a washing tub; a clutch connection device connected between a first set consisting of the pulsator and the washing shaft and a second set consisting of the dewatering shaft for transmitting the rotating force from the first or second set to the second or first set when the first or second set is rotated more than predetermined revolutions in one direction; and a friction member attached to at least one of the washing shaft, the dewatering shaft, and the clutch connection device for generating a frictional force when the rotating force is transmitted by the clutch connection device.
 17. The device as set forth in claim 16, wherein the clutch connection device comprises a coil spring.
 18. The device as set forth in claim 16, wherein the clutch connection device is connected between the washing shaft and the dewatering shaft.
 19. The device as set forth in claim 18, wherein the clutch connection device comprises a coil spring.
 20. The device as set forth in claim 16, wherein the washing shaft and the dewatering shaft are provided with elastic member mounting rings, respectively, to which both ends of the coil spring are fixedly mounted, respectively. 